Television news lit up in the United States in February of 1994 when a 31-year-old woman, Gloria Ramirez, died in a hospital emergency room. She'd been acutely ill with advanced cervical cancer, and when she began having pulmonary and respiratory problems, she called paramedics. Soon after she was brought to the emergency room at Riverside General Hospital in southern California, she passed out, and never regained consciousness. So far, there had been nothing unusual or medically out of the ordinary.

One the nurses drew blood from Ramirez, and noted that it both looked and smelled strange. It had an ammonia-like odor, and several people noticed manila-colored crystals floating in the blood. While the emergency room fought to reverse Ramirez' rapidly deteriorating condition, some of the staff began falling ill. Symptoms included dizziness and fainting, a sensation of burning on the skin, nausea, apnea, tremors, even paralysis. Ramirez died, and as her body was moved into isolation, those attending her also fell ill. The emergency room was evacuated to the parking lot. In all, 23 people became ill. Five were hospitalized. One nurse was kept in the hospital for ten days with tremors and apnea. The most seriously ill, a doctor in residence named Julie Gorchynski, stayed in intensive care for two weeks, contracting apnea, hepatitis, pancreatitis, and necrosis of the bone marrow which crippled her legs for months and required at least three surgeries.

Television crews arrived about the same time as the Riverside County hazardous materials team, and as southern California flew into a panic that a woman's body was knocking people out with its fumes, it was hardly noticed that the hazmat team came up empty handed. They found nothing unusual inside the emergency room. They searched for every kind of toxic substance they were equipped to find, and detected nothing that could account for the staff illnesses.

The task fell to the coroner, whose pathologists were charged with autopsying the toxic body. It was the most unusual autopsy the county had ever seen: doctors wearing full airtight suits with respirators, in a special sealed room. They took samples of everything: her tissue, her blood, even air from the bodybag she'd been in. And the final analysis? Nothing. The coroner's office found nothing inconsistent with a victim of cervical cancer, and like the hazmat team, nothing that would have knocked out the hospital staff or been harmful in any way.

The toxic lady, it turned out, was not toxic at all, by the all measures the doctors knew to employ.

And yet two members of the emergency room staff still lay in the hospital with undeniable physical medical conditions, and the rest of the staff all recalled the odors and strange looking blood. Something real had happened that night in February, and all the signs were that Gloria Ramirez, or something inside her, was the cause. Nevertheless, it couldn't be found with any certainty. Many investigations led to dead ends. And in September 1994, nearly seven months after the toxic lady felled the medical staff, the health department released its official report. Ramirez died from cervical cancer, and nothing else. The emergency room victims were found to be free of any explicable medical causes, and were determined to have suffered from a mass sociogenic illness, triggered by a frightening odor of unknown origin.

A sociogenic illness is one that is caused or influenced by social factors, rather than by a physical disease agent. It's a form of mass hysteria where the effect is a perceived illness. The concept of sociogenic illnesses is controversial, and labeling any event to be one always causes dissent and challenge. It's a diagnosis that almost nobody will accept.

During the 1990 gulf war when the first Iraqi SCUD missile struck Israel, 40% of the nearby civilians reported symptoms consistent with a gas attack, exactly as they expected; despite no chemical warhead being in the missile. In 1998, 800 Jordanian schoolchildren were vaccinated, and 122 were admitted to the hospital for what they believed were side effects; but for nearly all of them, no ill effects were found at all. Hundreds more schoolchildren fell ill in Belgium in 1999 after having drunk Coca-Cola, though nothing was found wrong with the beverage and none of the children had anything show up on blood tests. All three of these events are believed to be examples of sociogenic illness. In all cases, the epidemic was probably triggered by a very few victims who responded to some unknown triggering cause, probably a real reaction to something. But the cause was misinterpreted as whatever was obvious at the moment, and others who had been exposed to the same misinterpreted trigger experienced acute stress and fear, and the mass sociogenic illness was initiated.

Much about the Riverside toxic lady episode is consistent with this diagnosis. There were a number of startling surprises when Gloria Ramirez arrived at the emergency room. Besides the ammonia-like smell to her blood and the strange manila crystals in it, staff noticed that the skin on her abdomen had a weird oily appearance and smelled like garlic. Any one of these, or especially all of them together, might have triggered fear, nausea, or other stress reponses in the nurse who drew the blood, which she and others may have interpreted as a physical response to toxic gas. And notably, almost all of the victims were female, and females are historically far more susceptible to sociogenic illness, according to a literature survey published in the British Journal of Psychiatry in 2002. No toxic residue was found by the hazmat team or by the coroner's team. The paramedics who had answered Ramirez' call and brought her to the hospital also came into contact with her blood when they started an intravenous line, and reported no ill effects at all. Despite its seeming improbability for an experienced emergency room staff, the sociogenic illness explanation was not only a good fit for the toxic lady incident, it was almost an open-and-shut case.

But in spite of the official report, toxicology investigations had been going on behind the scenes the whole year. When the coroners found nothing, they enlisted some outside help from an impressive source: the Lawrence Livermore National Laboratory in northern California. Since there wasn't much doing in the cold war business in 1994, Livermore had set up a forensics lab to offer their expertise to law enforcement agencies who might need it.

While on center stage the sociogenic illness explanation was offered, and Dr. Gorchynski filed a $6 million lawsuit against the hospital, backstage the Livermore team was hard at work. To make a long story short, they finally pieced together a scenario that some see as plausible, and some not so much. Their breakthrough came from gas chromatograph mass spectrometer analysis of the samples from Ramirez, and also from the headspace, which is the air between the sample and the lid of the container. The spectrometer showed one surprising peak that couldn't be accounted for by the drugs Ramirez had been given: a concentration of dimethyl sulfone.

Dimethyl sulfone is one oxygen atom away from a similar chemical, dimethyl sulfoxide, commonly called DMSO. DMSO is sold as a gel in hardware stores as a powerful degreaser, and it's also used by athletes to rub onto sore muscles. In fact, many people put it on their skin to relieve pain from conditions like arthritis. It's not really great for you, but people do it anyway. DMSO also caught the attention of the Livermore researchers because it would explain the greasy appearance of Ramirez' torso and the garlic-like odor.

When the paramedics gave Ramirez oxygen in the ambulance, the high oxygen concentration in her blood would have combined with the DMSO they theorize she had self-administered to relieve pain from her cancer, and formed the dimethyl sulfone observed in the spectrometer results. Ramirez' family insisted that she did not take DMSO, but the spike on the spectrometer is pretty hard to argue with, and she certainly would not have been the first cancer patient to do that. Moreover, her cervical cancer had caused kidney failure (which is actually what killed her), and any DMSO would have built up to very high levels in her blood. In the Livermore researchers' tests to reproduce the process, dimethyl sulfone in blood — when cooled below body temperature by being withdrawn in a syringe — formed nice white crystals, which when viewed through blood plasma, were a dead ringer for the manila-colored crystals reported by the hospital staff.

The problem is that dimethyl sulfone wouldn't have hurt anyone, and this is where the Livermore findings have become a bit controversial. If some of the dimethyl sulfone molecules had broken down in her bloodstream, they would have combined with sulfates to form dimethyl sulfate, which is a powerful nerve gas. It produces all the same symptoms that struck the emergency room staff, with the exception of nausea. It even causes the hepatitis and pancreatitis that struck Julie Gorchynski. When the paramedics started the IV line in the ambulance, the conversion of DMSO to dimethyl sulfone was only just beginning and there would have not been any dimethyl sulfate nerve gas to affect them. But by the time the hospital staff worked on her, there was just enough to knock out those working close to the drawn blood, which is exactly what happened.

Some chemists find this conversion of dimethyl sulfone into dimethyl sulfate to be implausible, but the Livermore researchers argue that this would have inevitably happened to at least some small amount of it. It's impossible to know for sure if this is what happened to Gloria Ramirez, because if it had, all the suspect compounds except the dimethyl sulfone would have evaporated away or broken back down into constituents that are normally found in the body, effectively covering their tracks and eluding the hazmat teams and the coroners. By November, even People magazine reported that the mystery of the toxic lady had indeed been solved, citing Ramirez' use of DMSO as the ultimate cause.

So there were now two pretty solid theories left standing, the sociogenic illness and the DMSO. Neither is perfect, and both have sound criticism.

We don't know for an absolutely certainty, and probably never will, what caused the tragic events on that February night in Riverside. But a review of the facts shows that the title of "toxic lady" is unfair and undeserved. There was nothing toxic about Gloria Ramirez; just an all-too-young cancer victim doing her best to stay alive at the end of a painful and horrible illness. Hopefully we learned something from her case that will prevent future injuries.